Role description

The Hyper-V role enables you to create and manage a virtualized computing environment by using virtualization technology that is built in to Windows Server 2012 R2. Hyper-V virtualizes hardware to provide an environment in which you can run multiple operating systems at the same time on one physical computer, by running each operating system on its own virtual machine. For more information about Hyper-V, see the Hyper-V overview.

New and changed functionality

The following table lists functionality in Hyper-V that is new for this release or has been changed.

Shared virtual hard disk

This feature is used to build a high availability infrastructure, and it is especially important for private cloud deployments and cloud-hosted environments that manage large workloads. Shared virtual hard disks enable multiple virtual machines to access the same virtual hard disk (VHDX) file, which provides shared storage for use by Windows Failover Clustering.. The shared virtual hard disk files can be hosted on Cluster Shared Volumes (CSV) or on Server Message Block (SMB)-based Scale-Out File Server file shares.

What works differently?

This feature is new in Windows Server 2012 R2. It was not possible to cluster virtual machines by using a shared virtual hard disk in previous releases of Windows Server.

Resize virtual hard disk

Hyper-V storage has been updated to support resizing virtual hard disks while the virtual machine is running.

What value does this change add?

Resizing virtual hard disks while the virtual machine is running enables an administrator to perform configuration and maintenance operations on the virtual hard disks while the associated virtual machine is online or the virtual hard disk data disk is in use.

What works differently?

Online virtual hard disk resizing is only available for VHDX files that are attached to a SCSI controller. The virtual hard disk size can be increased or decreased through the user interface while virtual hard disk is in use.

Storage Quality of Service

Hyper-V in Windows Server 2012 R2 includes storage Quality of Service (QoS). Storage QoS enables you to manage storage throughput for virtual hard disks that are accessed by your virtual machines.

What value does this change add?

Storage QoS enables you to specify the maximum and minimum I/O loads in terms of I/O operations per second (IOPS) for each virtual disk in your virtual machines. Storage QoS ensures that the storage throughput of one virtual hard disk does not impact the performance of another virtual hard disk on the same host.

What works differently?

This feature is new in Windows Server 2012 R2. It was not possible to configure storage QoS parameters for your virtual hard disks in previous releases of Windows Server.

Live migrations

Hyper-V live migration has been updated with the following capabilities.

Improved performance

Hyper-V live migration has been updated to allow the administrator to select the optimal performance options when moving virtual machines to a different server.

What value does this change add?

In larger scale deployments, such as private cloud deployments or cloud hosting providers, this update can reduce overhead on the network and CPU usage in addition to reducing the amount of time for a live migration. Hyper-V administrators can configure the appropriate live migration performance options based on their environment and requirements.The following live migrations options are now available.

Option

Description

TCP/IP

The memory of the virtual machine is copied to the destination server over a TCP/IP connection. This is the same method that is used in Hyper-V in Windows Server 2012.

Compression

The memory content of the virtual machine that is being migrated is compressed and then copied to the destination server over a TCP/IP connection. This is the default setting in Hyper-V in Windows Server 2012 R2.

SMB 3.0 protocol

The memory content of the virtual machine is copied to the destination server over a SMB 3.0 connection.

SMB Direct is used when the network adapters on the source and destination servers have Remote Direct Memory Access (RDMA) capabilities enabled.

When moving a virtual machine, the specified destination server can now be a computer running Windows Server 2012 R2. This applies to a move that is initiated in Hyper-V Manager or when using the Move-VM Windows PowerShell cmdlet.

Virtual machine generation

Virtual machine generation determines the virtual hardware and functionality that is presented to the virtual machine.

Integration services

Hyper-V integration services are updated with a new service that allows Hyper-V administrators to copy files to the virtual machine while the virtual machine is running without using a network connection.

What value does this change add?

In previous versions of Hyper-V, a Hyper-V administrator may have needed to shut down a virtual machine to copy files to it. A new Hyper-V integration service has been added that allows the Hyper-V administrator to copy files to a running virtual machine without using a network connection.

What works differently?

A Windows PowerShell cmdlet, Copy-VMFile, also has been added for this new feature. The following services must be enabled for this feature to work.

Guest services on the Integration Services property page of the virtual machine needs to be selected. By default this setting is not selected.

Or you can enable the Guest services by using the Enable-VMIntegrationService Windows PowerShell cmdlet.

The Hyper-V Guest Service Interface service in the guest operating system must be running.

Note

The Hyper-V Guest Service Interface service enters a running state when the Guest services service is selected on the Integration Services property page of the virtual machine. To disable this feature in the guest operating system, the guest operating system administrator can set the Hyper-V Guest Service Interface service startup type to Disabled.

Export

Hyper-V is updated to support exporting a virtual machine or a virtual machine checkpoint while the virtual machine is running. You no longer need to shut down a virtual machine before exporting.

What value does this change add?

Exporting a virtual machine while the virtual machine is running allows the administrator to export the virtual machine without incurring any downtime.

This assists in the following scenarios:

Duplicating an existing production environment or part of an environment to a test lab.

Testing a planned move to a cloud hosting provider or to a private cloud.

Troubleshooting an application issue.

What works differently?

The Export option is now available as an action for a running virtual machine from Hyper-V Manager. The following Windows PowerShell cmdlets can be used on a running virtual machine, Export-VM and Export-VMSnapshot.

Failover Clustering and Hyper-V

Hyper-V has been enhanced to detect physical storage failures on storage devices that are not managed by Windows Failover Clustering (SMB 3.0 file shares). Storage failure detection can detect the failure of a virtual machine boot disk or any additional data disks associated with the virtual machine. If such an event occurs, Windows Failover Clustering ensures that the virtual machine is relocated and restarted on another node in the cluster. This eliminates situations where unmanaged storage failures would not be detected and where virtual machine resources may become unavailable.

Hyper-V and Windows Failover Clustering are enhanced to detect network connectivity issues for virtual machines. If the physical network assigned to the virtual machine suffers a failure (such as a faulty switch port or network adapter, or a disconnected network cable), the Windows Failover Cluster will move the virtual machine to another node in the cluster to restore network connectivity.

Enhanced session mode

Virtual Machine Connection in Hyper-V now allows redirection of local resources in a Virtual Machine Connection session.

What value does this change add?

Virtual Machine Connection enhances the interactive session experience provided for Hyper-V administrators who want to connect to their virtual machines. It provides functionality that is similar to a remote desktop connection when you are interacting with a virtual machine.

In previous versions of Hyper-V, Virtual Machine Connection provided redirection of only the virtual machine screen, keyboard, and mouse with limited copy functionality. To get additional redirection abilities, a remote desktop connection to the virtual machine could be initiated, but this required a network path to the virtual machine.

The following local resources can be redirected when using Virtual Machine Connection.

Display configuration

Audio

Printers

Clipboard

Smart cards

Drives

USB devices

Supported Plug and Play devices

What works differently?

This feature is enabled by default in Client Hyper-V, and it is disabled by default on Hyper-V in Windows Server.

The following guest operating systems support enhanced session mode connections:

Hyper-V Replica

Hyper-V Replica adds the following new features in Windows Server 2012 R2:

You can configure extended replication. In extended replication, your Replica server forwards information about changes that occur on the primary virtual machines to a third server (the extended Replica server). After a planned or unplanned failover from the primary server to the Replica server, the extended Replica server provides further business continuity protection. As with ordinary replication, you configure extended replication by using Hyper-V Manager, Windows PowerShell, or WMI.

The frequency of replication, which previously was a fixed value, is now configurable. You can also access recovery points for 24 hours. Previous versions had access to recovery points for only 15 hours.

Linux support

As part of Microsoft’s continuing commitment to making Hyper-V the best all-around virtual platform for hosting providers, there are now more built-in Linux Integration Services for newer distributions and more Hyper-V features are supported for Linux virtual machines.

What value does this change add?

Linux support for Hyper-V in Windows Server 2012 R2 has now been enhanced in the following ways:

Improved video - a Hyper-V-specific video driver is now included for Linux virtual machines to provide an enhanced video experience with better mouse support.

Dynamic Memory - Dynamic Memory is now fully supported for Linux virtual machines, including both hot-add and remove functionality. This means you can now run Windows and Linux virtual machines side-by-side on the same host machine while using Dynamic Memory to ensure fair allocation of memory resources to each virtual machine on the host.

Online backup - you can now back up running Linux virtual machines to Windows Azure using the Windows Azure Online Backup capabilities of the in-box Windows Server Backup utility, System Center Data Protection Manager, or any third-party backup solution that supports backing up Hyper-V virtual machines.

Management

You can manage Hyper-V in Windows Server 2012 from a computer running Windows Server 2012 R2 or Windows 8.1. In previous releases, you could not connect to and manage a down-level version of Hyper-V. A solution was to create a remote desktop session to a down-level server running Hyper-V and run the Hyper-V management operating system from within the remote desktop session. This solution required that Remote Desktop Services was running and properly configured, and the solution was not viable when Hyper-V was installed on Server Core installation.

What value does this change add?

You can manage Hyper-V in Windows Server 2012 from Hyper-V Manager in Windows Server 2012 R2 or Windows 8.1. This enables you to upgrade your management workstation to the latest version of the operating system and to connect and manage Hyper-V in Windows Server 2012.

You can deploy the latest version of Hyper-V without upgrading the management workstation immediately.

Note

When connecting to Hyper-V in Windows Server 2012 R2 from a computer running Windows Server 2012 or Windows 8, you can only perform actions that are supported by Hyper-V in Windows Server 2012.

Automatic Virtual Machine Activation

Automatic Virtual Machine Activation (AVMA) lets you install virtual machines on a computer where Windows Server 2012 R2 is properly activated without having to manage product keys for each individual virtual machine, even in disconnected environments. AVMA binds the virtual machine activation to the licensed virtualization server and activates the virtual machine when it starts. AVMA also provides real-time reporting on usage, and historical data on the license state of the virtual machine. Reporting and tracking data is available on the virtualization server.

Track virtual machine usage and licenses from the virtualization server, without requiring any access rights on the virtual machines

What works differently?

There are no product keys to manage and no stickers to read on the servers. The virtual machine is activated and continues to work even when it is migrated across an array of virtualization servers.

Service Provider License Agreement (SPLA) partners and other hosting providers do not have to share product keys with tenants or access a tenant’s virtual machine to activate it. Virtual machine activation is transparent to the tenant when AVMA is used. Hosting providers can use the server logs to verify license compliance and to track client usage history.